BR112020005453A2 - seismic sensor - Google Patents

Abstract

A seismic sensor includes an external housing that has a central axis, an upper end, a lower end and an internal cavity. In addition, the seismic sensor includes a test piece movably positioned in the internal cavity of the external housing. The external housing is configured to move axially in relation to the test mass. In addition, the seismic sensor includes a first tensioning element positioned in the internal cavity and positioned axially between the test mass and one end of the external housing. The first tensioning element is configured to flex in response to the axial movement of the outer housing in relation to the test mass. The first tensioning element comprises a disk that includes a plurality of circumferentially spaced grooves that extend axially through it. In addition, the seismic sensor includes a sensor element positioned in the internal cavity and axially positioned between the first tensioning element and one of the ends of the external housing. The sensor element includes a piezoelectric material configured to deflect and generate a potential in response to the axial movement of the external housing in relation to the test mass and the flexing of the first tensioning element.

Description

Descriptive Report of the Invention Patent for "SYSMIC SENSOR".

BACKGROUND

[001] The description refers, in general, to devices for carrying out seismic surveys. More particularly, the description refers to seismic sensors or nodes.

[002] The seismic survey, or reflection seismology, is used to map the Earth's subsoil. A controlled seismic source emits low frequency seismic waves that move through the Earth's subsoil. At the interfaces between different rock layers, the seismic waves are partially reflected. The reflected waves return to the surface, where they are detected by one or more seismic sensors. In particular, seismic sensors detect and measure vibrations induced by waves. Ground vibrations detected by seismic sensors on the ground surface can have a very wide dynamic range, with displacement distances ranging from centimeters to angstroms. The data recorded by the seismic sensors are analyzed to reveal the structure and composition of the subsoil.

[003] Conventional seismic sensors (for example, geophones) are, in general, manufactured with an electric coil of wire immersed in a strong magnetic field. These electromagnetic sensors can be constructed as moving magnets or moving coils. In the mobile coil version, the magnet is attached to the housing which is then firmly placed on the ground. The moving electric coil is immersed in the space of the magnetic field of the fixed magnet and the coil is loosely coupled to the external housing of the sensor by soft springs that restrict the movement of the coil along a single axis. As the coil moves in relation to the fixed magnet, it progressively cuts the magnetic flux lines, generating a voltage and current at the coil's electrical terminals in proportion to the travel speed on the ground (for example,

vibrations). In the mobile coil type, the coil defines the mass in the seismic sensor that moves in response to vibrations in the ground.

[004] Another type of seismic sensor depends on the capacitance to generate the electrical signal. These are typically built as micro-electromechanical systems (MicroElectroMechanicals, MEMs) that use micro-machined silicon with metallic coating applied to opposite components on opposite sides of a small, spring-loaded mass. These MEM sensors generally have the advantage of small size and weight when compared to a moving coil geophone. The movement of the test mass in the MEMs in relation to the fixed external plates creates a variable capacitance that is detected as a signal proportional to the acceleration of the sensor displacement.

BRIEF SUMMARY OF THE INVENTION

[005] Seismic sensor modalities are described here. In one embodiment, a seismic sensor comprises an external housing that has a central axis, an upper end, a lower end and an internal cavity. In addition, the seismic sensor comprises a test mass placed in a mobile manner in the internal cavity of the external housing. The external housing is configured to move axially in relation to the test mass. In addition, the seismic sensor comprises a first tensioning element positioned in the internal cavity and positioned axially between the test mass and one end of the external housing. The first tensioning element is configured to flex in response to the axial movement of the outer housing in relation to the test mass. The first tensioning element comprises a disk that includes a plurality of circumferentially spaced grooves extending axially through it. In addition, the seismic sensor comprises a sensor element positioned in the internal cavity and axially positioned between the first tensioning element and one of the ends of the external housing. The sensor element comprises a piezoelectric material configured to deflect and generate an electrical potential in response to the axial movement of the external housing in relation to the test mass and the flexing of the first tensioning element.

[006] In another embodiment, a seismic sensor for a seismic survey comprises an external housing that has a central axis. In addition, the seismic sensor comprises a test mass placed in a mobile manner in the external housing. The test mass comprises a power supply. In addition, the seismic sensor comprises a disk-shaped sensor element positioned in the outer housing and configured to detect the movement of the outer housing in relation to the test mass. In addition, the seismic sensor comprises electronic circuits coupled to the sensor element. In addition, the seismic sensor comprises a first tensioning element and a second tensioning element that supports the test mass inside the external housing. The second tensioning element is axially positioned between the test mass and the sensor element. Each tensioning element comprises a conductive elastic disk that has a central region coupled to the test mass and a radially external periphery coupled in a fixed manner to the external housing. Each tensioning element is configured to flex in an axial direction and resist flexing in a radial direction. Each tensioning element electrically couples the power supply to the electronic circuit.

[007] Here are described modalities of methods to detect seismic waves that pass through an underground formation. In one embodiment, a method comprises (a) coupling a seismic survey device in contact with the ground above the underground formation. The seismic survey device comprises an external housing that has a longitudinal axis, an upper end, a lower end and an internal cavity. The seismic survey device also comprises a test mass movably positioned in the internal cavity of the external housing. In addition, the seismic survey device comprises a first tensioning element positioned in the internal cavity and positioned axially between the test mass and the lower end of the external housing. In addition, the seismic survey device comprises a sensor element positioned in the internal cavity and positioned axially between the test mass and the lower end of the outer housing or the upper end of the outer housing. The method also comprises (b) orienting the seismic survey device with the longitudinal axis of the housing in a vertical orientation. In addition, the method comprises (c) moving the outer housing vertically in relation to the body in response to seismic waves. In addition, the method comprises (d) axially flexing the first tensioning element in response to (c). In addition, the method comprises (e) deflecting the sensor element during (d). The method also comprises (f) generating a signal with the sensor element indicative of the vertical movement of the external housing in relation to the test mass during (c) in response to (e).

[008] Modalities described here comprise a combination of characteristics and advantages aimed at addressing various deficiencies associated with certain devices, systems and previous methods. The foregoing described the technical characteristics and advantages of the invention quite broadly, so that the following detailed description of the invention can be better understood. The various features described above, as well as other features, will be readily apparent to those skilled in the art when reading the detailed description below and in reference to the attached drawings. It will be appreciated by those skilled in the art that the design and the specific modalities described can readily be used as a basis for modifying or designing other structures to achieve the same objectives as the invention. It will also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention, as presented in the attached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[009] For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:

[0010] Figure 1 is a schematic view of a seismic detection system that includes a plurality of seismic sensors;

[0011] Figure 2 is a perspective view of a seismic sensor modality according to the principles described here;

[0012] Figure 3 is a longitudinal sectional view of the seismic sensor in Figure 2;

[0013] Figure 4 is a perspective end view of the end cap of Figure 2;

[0014] Figure 5 is an enlarged partial cross-sectional view of the seismic sensor of Figure 2 that illustrates the coupling between the cover and the body of the external housing;

[0015] Figure 6 is a perspective view of the inductive coil assembly of Figure 3;

[0016] Figure 7 is a side perspective view of the carrier of Figure 3;

[0017] Figure 8 is a side perspective view of the carrier of Figure 3;

[0018] Figure 9 is an enlarged sectional view of the seismic sensor of Figure 2;

[0019] Figure 10 is an enlarged perspective view of the lower connection element and the sensor element of Figure 3;

[0020] Figure 11 is a partial cross-sectional perspective view of the seismic sensor of Figure 2;

[0021] Figure 12 is a perspective view of the battery and circuit board of Figure 3;

[0022] Figure 13 is an enlarged perspective view of the battery, the circuit board and a tab of Figure 3;

[0023] Figure 14 is a perspective view of a seismic sensor modality according to the principles described here;

[0024] Figure 15 is a longitudinal sectional view of the seismic sensor of Figure 14;

[0025] Figure 16 is a partial sectional view in top perspective of the seismic sensor of Figure 14;

[0026] Figure 17 is an enlarged partial sectional view of the seismic sensor of Figure 14;

[0027] Figure 18 is an enlarged sectional view of the seismic sensor of Figure 14;

[0028] Figure 19 is a partial sectional view in enlarged perspective of the seismic sensor of Figure 14;

[0029] Figure 20 is an enlarged sectional view of the seismic sensor of Figure 14;

[0030] Figure 21 is a perspective view of the battery and tabs of Figure 16; and

[0031] Figure 22 is a top view of an embodiment of a guide according to the principles described here.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0032] The following discussion is directed to several exemplary modalities. However, those skilled in the art will understand that the examples described here have wide application and that the discussion of any modality is just an example of such a modality and is not intended to suggest that the scope of the invention, including the claims, is limited to such modality.

[0033] Certain terms are used throughout the description and claims below to refer to specific characteristics or components. As those skilled in the art will realize, different people may refer to the same characteristic or component by different names. This document is not intended to distinguish between components or features that differ in name, but not function. The figures in the drawing are not necessarily to scale. Certain features and components contained here may be shown in an exaggerated scale or in a somewhat schematic manner and some details of conventional elements may not be shown in the interest of clarity and conciseness.

[0034] In the following discussion and in the claims, the terms "that include" and "that comprises (m)" are used in an open manner and, therefore, should be interpreted as "including, but without limitations ...". In addition, the term "pair" or "pairs" is intended to mean an indirect or direct connection. Thus, if a first device is coupled to a second device, this connection can be through a direct or indirect connection through other devices, components and connections. In addition, as used here, the terms "axial" and "axially" generally mean along or parallel to a central axis (for example, the central axis of a body or a door), while the terms "radial" and "radially" mean, in general, perpendicular to the central axis. For example, an axial distance refers to a distance measured along or parallel to the central axis and a radial distance means a distance measured perpendicular to the central axis. Any reference up or down in the description and claims will be made for the sake of clarity, with "above", "top", "up" "below", "bottom" and "down" meaning the position or direction in normal use.

[0035] Referring now to Figure 1, a schematic representation of a seismic survey system 50 for surveying an underground rock formation 51 is shown. As shown in Figure 1, the subsoil 51 has a relatively uniform composition, with the exception of the layer 52 which can be, for example, a different type of rock compared to the rest of the subsoil 51. As a result, layer 52 can have a density, elastic speed, etc. different compared to the rest of the subsoil 51.

[0036] The survey system 50 includes a seismic source 54 positioned on the surface 56 of the soil and a plurality of seismic sensors 64, 66, 68 firmly coupled to the surface 56. Seismic source 54 generates and produces controlled seismic waves 58, 60 62 which are directed downwards in the subsoil 51 and propagate through the subsoil

51. In general, seismic source 54 can be any suitable seismic source known in the art including, without limitation, explosive seismic sources, vibrating trucks and accelerated weight-loss systems, also known as dump trucks. For example, a dump truck can hit the surface 56 of the ground with a weight or "hammer", creating a shock that spreads through the subsoil 51 like seismic waves.

[0037] Due to the differences in density and / or elastic speed of layer 52 compared to the rest of the subsoil 51, seismic waves 58, 60, 62 are reflected, at least partially, from the surface of layer 52. The waves reflected seismic 58 ', 60', 62 'propagate upward from layer 52 to surface 56, where they are detected by seismic sensors 64, 66, 68.

[0038] Seismic source 54 can also induce surface interface waves 57 which, in general, travel along surface 56 at relatively slow speeds and are detected simultaneously with reflected seismic waves 58 ', 60', 62 'deeper. Surface interface waves 57 generally have a greater amplitude than reflected seismic waves 58 ', 60', 62 'due to the cumulative effects of energy loss during the propagation of reflected seismic waves 58', 60 ' , 62 ', such as geometric dispersion of the wavefront, loss of interface transmission, weak reflection coefficient and absorption of the displacement path. The cumulative effect of these losses can reach 75 dB and, in cases above 100 dB, the difference in amplitude between the various waveforms registered by sensors 64, 66, 68.

[0039] The sensors 64, 66, 68 detect the various waves 57, 58 ', 60', 62 'and then store and / or transmit data indicative of the waves 57, 58', 60 ', 62' detected. This data can be analyzed to determine information about the composition of subsoil 51, such as the location of layer 52.

[0040] Although the seismic survey system 50 is shown and described as a surface or terrestrial system, the modalities described here can also be used in relation to seismic surveys in transition zones (for example, swamps or swamps, water areas shallows, such as between the ground and the sea) and marine seismic survey systems in which the rock formation subsoil (eg subsoil 51) is covered by a layer of water. In sea-based systems, seismic sensors (for example, seismic sensors 64, 66, 68) can be positioned on or on the seabed or, alternatively, on or in the water. In addition, in such marine systems, alternative types of seismic sources (for example, seismic sources 54) can be used including, without limitation, air guns and plasma sound sources.

[0041] Referring now to Figures 2 and 3, a modality of a seismic sensor 100 is shown. In general, the seismic sensor 100 can be used in any seismic survey system. For example, sensor 100 can be used for any one or more of sensors 64, 66, 68 of seismic survey system 50 shown in Figure 1 and described above. Although sensor 100 can be used in terrestrial or marine seismic surveying systems, it is particularly suitable for terrestrial seismic surveys.

[0042] In this embodiment, the seismic sensor 100 includes an outer housing 101, an inductive coil assembly 130 positioned within housing 101, a conveyor 140 positioned in housing 101 adjacent to inductive coil assembly 130 and a sensor element 180 positioned within the housing 101 and coupled to conveyor 140. A supply or power supply 190 and electronic circuit 195 are removably mounted on conveyor 140 within housing 101. In this embodiment, power supply 190 is a battery and electronic circuit 195 is in the form of a circuit board (for example, PCB). Thus, power supply 190 can also be referred to as battery 190 and electronic circuit 195 may also be referred to as circuit board 195.

[0043] Still with reference to Figures 2 and 3, the housing 101 has a central or longitudinal axis 105, a first or upper end 101a, a second or lower end 101b and an inner chamber or cavity 102. As will be described in more detail below, in this embodiment, the ends 101a, 101b are closed and the internal cavity 102 is sealed and isolated from the surrounding environment, outside the sensor 100, thus protecting the sensitive components positioned inside the housing 101 of the environment (for example, water, dirt, etc.).

[0044] In this embodiment, the housing 101 includes a body generally in the shape of a cup 110 and an inverted cover in the shape of a cup 120 fixedly attached to the body 110. In particular, the body

110 has a central or longitudinal axis 115 coaxially aligned with the axis 105, a first end or upper end 110a and a second end or lower end 110b that defines the lower end 101b of housing 101. In addition, body 110 includes a cylindrical base flat 111 at the lower end 110b and a tubular sleeve 112 extending axially upwardly from the base 111 to the upper end 110a. The base 111 closes the sleeve 112 at the lower end 110b, however, the sleeve 112 and the body 110 are opened at the upper end 110a. As a result, the body 110 includes a receptacle 113 that extends axially from the upper end 110a to the base 111. The receptacle 113 is part of the inner cavity 102 of the housing 101. As will be described in more detail below, the upper end open 110a is closed with the cap 120. An annular flange 116 extends radially out of sleeve 112 at the upper end 110a and an elevated annular lip or shoulder 117 extends axially upward from base 111 to cavity 113. In this embodiment , the entire body 110 (including the base 111, sleeve 112 and flange 116) is made through injection molding in a single piece of polycarbonate.

[0045] With reference now to Figures 2-4, cover 120 has a central or longitudinal axis 125 coaxially aligned with axis 105, a first or upper end 120a that defines the upper end 101a of housing 101 and a second or lower end 120b. In this embodiment, the lid 120 has the general shape of an inverted cup. In particular, the cap 120 includes a flat cylindrical upper part 121 at the upper end 120a and a tubular sleeve 122 which extends axially downwardly from the upper part 121 to the lower end 120b. The upper part 121 closes the sleeve 122 at the upper end 120a, however, the sleeve 122 and the cap 120 are opened at the lower end 120b. As a result, the cap 120 includes an inner chamber or cavity 123 that extends axially from the lower end 120b to the upper part 121. An annular flange 126 extends radially outwardly from the sleeve 122 proximal to the lower end 120b. In addition, an elongated cylindrical light guide 127 extends axially downwardly from the top 121 to the cavity 113. The guide 127 is coaxially positioned within the cap 120 (for example, the guide 127 has a central axis coaxially aligned with the axis 125) and has a first or upper end 127a fixedly attached to the upper part 121 and a second or lower end 127b distal to the upper part 121b.

[0046] As will be described in more detail below, guide 127 is part of a set of light guides for wireless data communication to / from circuit board 195 through the upper part 121 via light transmission. In the modalities described here, the light transmitted by the set of light guides has a frequency in the visible or infrared range of the electromagnetic spectrum (for example, frequency from 3.0 THz to 300.0 THz and wavelength from 1.0 um to 100 um). In one embodiment, the light transmitted by the set of light guides is in the infrared range of the electromagnetic spectrum with a wavelength of 850 nm. To facilitate the transmission of light through the guide 127, it is made of a clear / transparent material and, to facilitate the transmission of light through the upper part 121, it is made of a clear / transparent material. In this embodiment, the entire cover 120 (including the upper part 121, the sleeve 122 and the guide 127) is made through injection molding in a single piece of transparent polycarbonate.

[0047] As best shown in Figures 2 and 3, in this embodiment, a connector 128 is located on the outside of cover 120 at the upper end 120a. In this modality, connector 128 is an eye connector or through hole to which a cable, cord, hook,

carabiner or similar can be removably attached. This can facilitate the transport of the sensor 100 during implantation and recovery and / or facilitate the location of the sensors 100 for recovery.

[0048] With reference now to Figure 3, the cap 120 is fixedly attached to the body 110. In particular, the cap 120 is aligned coaxially with the body 110 with the lower end 120b of the cap 120 seated on the upper end 110a of the body 110 and annular flanges 116, 126 axially supporting each other. The body 110 and the cover 120 are dimensioned so that an interference fit is provided between the lower end 120b of the cover 120 and the upper end 110a of the body 110 when the lower end 120b is seated on the upper end 110a. In this embodiment, the body 110 and the cap 120 are made of the same material (polycarbonate) and therefore can be ultrasonically welded together to securely attach the cap 120 to the body 110. More specifically, an annular ultrasonic weld W110-120 is formed between the radially opposite outer surface and the radially inner surface of the sleeves 122, 112, respectively, at the ends 120b, 110a. The Wi10-120 weld defines a primary annular seal between cap 120 and body 110 that prevents fluid communication between cavities 113, 123 and the environment around sensor 100. In this embodiment, a secondary or backup annular seal set 129 is located between cover 120 and body 110. Seal assembly 129 includes an annular O-ring seal seated in an annular recess located on the bottom surface of flange 126. The O-ring seal is axially compressed between flanges 116 , 126.

[0049] With reference now to Figures 3 and 6, the inductive coil assembly 130 is used to inductively charge battery 190 from the outside of sensor 100 (for example, wireless). In this embodiment, the inductive coil assembly 130 includes a sleeve-shaped cylindrical body 131 and a coil 136 wrapped around body 131. Coil 136 is electrically coupled to circuit board 195 with wires (not shown) that allow transfer of current for circuit board 195 which, in turn, charges battery 190 during charging operations.

[0050] The body 131 has a central axis 135, a first end or upper end 131a and a second end or lower end 131b. As best shown in Figure 3, the assembly 130 is positioned inside the cover 120 with the axes 135, 105 coaxially aligned. As shown in Figure 6, the upper end 131a is opened, while a disc 132 extends through the lower end 131b. The disc 132 is, in general, perpendicularly oriented to the axis 135 and includes a central hole 133. The radially external surface of the body 131 includes an annular recess 134 that extends axially between the ends 131a, 131b. Coil 136 is seated in recess 134 with coil 136 coils axially adjacent to each other. A pair of circumferentially spaced latches 137 and a pair of circumferentially spaced guides 138 extend axially downwardly from the lower end 131b. Latches 137 releasably secure coil assembly 130 to conveyor 140 so that assembly 130 cannot move in rotation or translation with respect to conveyor 140 and guides 138 slide into an internal surface of conveyor 140 to facilitate the coaxial alignment of the body 131 and the conveyor 140 during the installation of the assembly 130. In this embodiment, the guides 138 are evenly spaced on the periphery by 18 º and the locks 137 are uniformly spaced on the periphery by 180º, with a guide 138 positioned between each pair of circumferentially adjacent locks 137.

[0051] Referring now to Figures 3, 7 and 8, the conveyor 140 reliably supports the sensor element 180, the battery 190 and the circuit board 195 inside the body 111 of the external housing 110 and operates on the sensor element 180 in response to vibrations induced by seismic waves. In this embodiment, the conveyor 140 has a central or longitudinal axis 145, a first end or upper end 140a, a proximal upper end 111a of the body 111 and a second end or lower end 140b seated against the shoulder 117 of the body 110. As best shown in Figure 3, the conveyor 140 is positioned inside the body 110 with the axes 145, 105 coaxially aligned.

[0052] Referring now to Figures 7 and 8, in this embodiment, the conveyor 140 includes an upper connecting element 150 at the upper end 140a, a lower connecting element 160 at the lower end 140b and a battery holder 170 axially positioned between the elements 150, 160. An elongated upper column 141 couples the upper connecting element 150 to the battery holder 170 and an elongated lower column 142 couples the lower connecting element 160 to the battery holder 170. Thus, the column 141 is axially positioned between the battery holder 170 and the upper connection element 150 and the column 142 are axially positioned between the battery holder 170 and the lower connection element 160. In this embodiment, the connection elements 150, 160, the support 170 and the columns 141, 142 are positioned concentrically and aligned coaxially with the housing 101. In addition, in this embodiment, the connecting elements 150, 160, the support 170 and the columns 141, 142 are sound o monolithically formed as a unitary piece. In particular, in this embodiment, the entire conveyor 140 is made as a monolithic piece through injection molding in a single piece of transparent polycarbonate.

[0053] The upper connecting element 150 has a first end or upper end 150a that defines the upper end 140a of the conveyor 140 and a second end or lower end 150b opposite the end 150a. In addition, the upper connecting element 150 includes an annular body 151 which extends axially between the ends 150a, 150b, a bending or tensioning element 152 mounted on the body 151 at the lower end 150b and a generally annular mounting flange 153 which extends radially outwardly from the body 151 at the lower end 150b. A pair of uniformly spaced circumferentially holes 154 extends radially through the body 151. The guides 138 of the inductive coil assembly 130 are positioned (for example, dimensioned and positioned) to slide into the inner surface of the sleeve 151 at the top end 150a , while the locks 137 releasably engage the holes 154, thus aligning and connecting the assembly 130 and the connecting element 150.

[0054] With reference again to Figures 7 and 8, the mounting flange 153 extends radially outwardly from the body 151. In this embodiment, the flange 153 is not a continuous annular flange, however, it includes a plurality of extension segments circumferential 153a. Each segment 153a has a radially outer cylindrical surface 153b positioned at substantially the same radius as the inner surface of sleeve 112 of body 110. In particular, the cylindrical surfaces 153b of segments 153a are fixedly attached to sleeve 112 at the proximal upper end 110a, as shown in Figure 3. In general, segments 153a can be attached to sleeve 112 by any suitable means known in the art including, without limitation, adhesive, interference fit, welded connection, etc. In this embodiment, the upper connection element 150 and the housing 110 are made of polycarbonate and therefore the segments

153a are ultrasonically welded to sleeve 112 along surfaces 153b.

[0055] The seismic sensor 100 can be provided with an electromagnetic shield. Electromagnetic shielding is known in the art and can protect the sensor components from radio frequency signals external to the sensor, which could interfere with the operation of the components.

[0056] With reference now to Figures 3, 5 and 7, the tensioning element 152 is a flexible and resilient element that flexes and deforms elastically in response to the relative movement of the external housing 101 in relation to the battery support 170 and the assembled components on it (for example, battery 190 and circuit board 195). In this embodiment, the tensioning element 152 comprises an annular disk or flange 156 that includes a plurality of cuts or grooves 157 uniformly spaced circumferentially. Each groove 157 extends axially through disc 156. In addition, each groove 157 spirals radially outwardly when moving from a radially inner end proximal to the center of disc 156 and a body proximal to the radially outer end 151. In this embodiment, three grooves 157 are provided, each pair of circumferentially adjacent inner ends of grooves 157 is angularly spaced 120 ° to axis 145, each pair of circumferentially adjacent outer ends of grooves 157 is angularly spaced 120 ° to axis 145 and each groove 157 extends along a spiral angle measured around axis 145 between its ends of about 180 °. As used herein, the term "spiral angle" refers to the angle measured around an axis between the end ends of an object (for example, angle measured around axis 145 between the ends of a groove 157). The radially internal ends of the grooves 157 are radially spaced from the center of the disc 156 and the axis 145. As a result, a central portion of the disc 156 constitutes a solid region on the disc 156 to which the upper end of the column 141 is fixedly attached. .

[0057] The tensioner 152 tilts the battery holder 170 radially and the components mounted thereon to a radially spaced central or concentric position of the housing 101, but does not substantially support or support the weight of the battery holder 170 and the components mounted on the same. Thus, the tensioning element 152 yields to the weight of the battery support 170 and the components mounted on it. In particular, disk 156 is a semi-rigid structure that generally resists bending and flexing. However, the presence of spiral grooves 157 increases the flexibility of the disc 156 in the region along which the grooves 157 are positioned (for example, the region positioned radially between the column 141 and the segments 153a), allowing the region to flex in the axial direction (up and down) relatively easily. The spiral grooves 157 also increase the flexibility of the disc 156 in the radial direction. However, the spiral grooves 157 do not allow the disc 156 to flex so easily in the radial direction. Due to the relatively high degree of flexibility of the tensioning element 152 in the axial direction, when an axial load is applied to the tensioning element 152 by the column 141, the grooves 157 generally allow the central portion of the disc 156 to move axially freely upwards and down in relation to segments 153a. However, due to the more limited flexibility in the radial direction, when a radial load is applied to the tensioner element 152 by the column 141, the grooves 157 generally prevent the central portion of the disc 156 from moving radially in relation to segments 153a and, even the limited extent in which the central portion of the disc 156 moves radially, the disc 156 pushes the central portion and the column 141 back into coaxial alignment with the axes 105, 145.

[0058] As best shown in Figures 3 and 8, in this embodiment, an elongated and curved L-shaped light guide 143 is coupled to the upper connecting element 150. The light guide 143 has a first end 143a proximal to the plate circuit 195, a second end 143b proximal to the lower end 127b of light guide 127, a first or horizontal portion 144a extending radially from end 143a, a second or vertical portion 144b extending axially from end 143b and a 90 ° curve or curvature that extends between portions 144a, 144b. The vertical portion 144b extends through the center of the disk 156 of the tensioner element 152 and the hole 133 of the coil assembly 130 and is coaxially aligned with the light guide 127 and the housing 101. Similar to the light guide 127, to facilitate the light transmission, the guide 143 is made of a clear / transparent material, such as transparent polycarbonate. As will be described in more detail below, light guides 127, 143 form the light guide set that wirelessly communicates data to / from circuit board 195 to the top 121. A Gg space is located axially between the ends 127b, 143b to allow relative axial movement between the light guides 127, 143. The space Gg has an axially measured height between the ends 127b, 143b which is preferably minimized to reduce the loss of light transmitted between the guides of light 127, 143 through the space Gg, allowing sufficient relative axial movement between the light guides 127, 143, as will be described in more detail below. In this embodiment, the relative axial movement of the light guides 127, 143 is about 10.0 microns and, therefore, the Gg space is preferably at least 10 microns.

[0059] Referring now to Figures 3 and 7-10, the lower connecting element 160 includes an annular mounting flange 161 and a bending or tensioning element 162 mounted on flange 156. In this embodiment, flange 161 is not a flange continuous annular, however, includes a plurality of circumferential length segments 161a. Each segment 161a has a radially outer cylindrical surface 161b positioned at substantially the same radius as the inner surface of sleeve 112 of body 110. In particular, the cylindrical surfaces 161b of segments 161a are fixedly attached to sleeve 112 proximal to the lower end 110b, as shown in Figure 9. In general, segments 161a can be attached to sleeve 112 by any suitable means known in the art including, without limitation, adhesive, interference fit, welded connection, etc. In this embodiment, the lower connecting element 160 and the housing 110 are made of polycarbonate and, therefore, segments 161a are ultrasonically welded in sleeve 112 along surfaces 161b. As best shown in Figures 8 and 10, flange 161 includes a pair of circumferentially spaced resilient fingers 163 that can be flexed radially outward to position the sensor element 180 within the flange 156 and then allowed to return radially inward to maintain the sensor element 180 in the desired position within flange 161.

[0060] With reference now to Figures 7-9, the tension element 162 is similar to the tension element 152 previously described. In particular, the tensioning element 162 is a resilient element that flexes and deforms elastically in response to the relative movement of the outer housing 101 in relation to the battery holder 170 and the components mounted thereon (for example, battery 190 and circuit board 195) . In addition, the tensioning element 162 comprises an annular disk or flange 156, as previously described. The lower end of the column 142 is fixedly attached to the solid central region of the disc 156 of the tension element 162. However, in this embodiment, the tension element 162 includes a semi-spherical deflection inductor or button 164 and an annular support lip or crest which extends axially from the bottom of the disc 156. The button 164 is centered on the disc 156 and the lip 166 is coaxially aligned with the disc 156. In addition, the lip 166 is radially positioned between the grooves 157 and the flange of assembly 161. The button 164 and the lip 166 extend the same axially measured distance from the bottom of the disc 156.

[0061] With reference now to Figures 9 and 10, the sensor element 180 is a flat disc seated inside the mounting flange 161 against the button 164 and the lip 166 - the tip of the button 164 engages in the center of the upper surface of the sensor element 180 and lip 166 engages the radially outer periphery of the upper surface of the sensor element

180. Fingers 163 hold sensor element 180 within flange 161 against button 164 and lip 166. As best shown in Figure 9, shoulder 117 of body 110 is positioned in the same radius as lip 166 and engages the radially outer periphery from the lower surface of the sensor element 180 axially opposite the lip 166. Thus, the outer periphery of the sensor element 180 is compressed and fixed in the position between the shoulder 117 and the lip 166.

[0062] In the same way as the tensioning element 152 previously described, the tensioning element 162 radially pushes the battery support 170 and the components mounted on it to a radially spaced central or concentric position of the housing 101, but does not substantially support or support the weight of the battery holder 170 and the components mounted on it. Thus, the tensioning element 162 yields to the weight of the battery support 170 and the components mounted thereon. Due to the relatively high degree of flexibility of the tensioning element 162 in the axial direction, when an axial load is applied to the tensioning element 162 by the column 142, the grooves 157 generally allow the central portion of the disc 156 to move axially free upwards and down in relation to segments 153a. However, due to the more limited flexibility in the radial direction, when a radial load is applied to the tensioning element 162 by the column 142, the grooves 157 generally prevent the central portion of the disc 156 from moving radially in relation to the segments 161a and even the limited extent that the central portion of the disc 156 moves radially, the disc 156 pushes the central portion and the column 142 back into coaxial alignment with the axes 105, 145.

[0063] The annular flanges 153, 161 are fixedly attached to the external housing 101 and to the columns 141, 142 coupled to the battery support 170 to urge the tension elements 152, 162, respectively. Thus, the weight of the battery support 170 and the components mounted on it cause the tension elements 152, 162 to flex and sag in the axial direction, thus placing the tip of the button 164 in contact with the center of the sensor element 180 and transferring substantially the entire weight of the battery holder 170 and the components mounted on it to the center of the sensor element 180 (via button 164).

[0064] As best shown in Figure 9, the tip of the button 164 contacts the center of the sensor element 180 and transfers the weight of the battery holder 170 and the components mounted on it to the sensor element 180 with the external housing 101 and the battery holder 170 at rest (e.g., no relative movement between the outer housing 101 and the battery holder 170). The outer periphery of the sensor element 180 is contained between the lip 166 and the shoulder 117 and, thus, when the button 164 is supported against the sensor element 180 under the weight of the battery support 170 and the components mounted on it, the external periphery of the sensor element 180 is static in relation to the housing 101.

[0065] Referring again to Figures 7 and 8, the battery holder 170 has a first end or upper end 170a and a second end or lower end 170b. In addition, the battery holder 170 includes a first wall or upper part 171 positioned at the upper end 170a, a second wall or lower part 172 positioned at the lower end 170b and a semi-cylindrical body 173 which extends axially between the walls 171, 172. Each wall 171, 172 is an annular plate or disk that includes a rectangular recess 174 that extends radially inward from the radially outer edge of the disk. The recesses 174 of the walls 171, 172 are circumferentially aligned and dimensioned to receive the circuit board 195, as shown in Figure 11. As best shown in Figure 3, each wall 171, 172 has an external radius that is less than the radius inner of the outer housing 101. Thus, a space Gr is radially located between each wall 171, 172 and the housing 101. Each space Gr has a radially measured width between the wall 171, 172 and the outer housing 101. In the modalities described here, the radial width of each space Gr is preferably greater than 0.0 mm (for example, different from zero) and less than 2.0 mm and, more preferably, greater than 0.0 mm and less than than 1.0 mm, with the battery holder 170 positioned concentrically in the outer housing 101. The space Gr allows the outer housing 101 to move radially and laterally in relation to the battery holder 170 as the discs 156 of the tensioning elements 152 , 162 flex, however , limit the maximum of this radial and lateral movement. Thus, walls 171, 172 function as radial movement limiters or stops - battery holder 180 can move radially within housing 101 until wall 171, 172 contacts radially with housing 101.

[0066] Referring again to Figures 7 and 8, a pair of uniformly spaced circumferentially columns 176 extends axially from the radially outer periphery of each wall 171, 172. Columns 176 of the upper wall 171 extend axially upward towards the tensioning element 152 and columns 176 of the wall 172 extend axially downwards towards the tensioning element 162. However, the terminal ends of the columns 176 are axially spaced from the axially adjacent tensioning elements 152, 162. Thus, a space Ga is positioned axially between the end of each column 176 and the axially adjacent tension element 152, 162. Each space Ga has an axially measured height between the end of each column 176 and the axially adjacent tension element 152, 162. In the embodiments described here, the axial height of each Ga space is preferably about 10.0 microns, with the battery holder 170 in the neutral position in the housing external 101. As will be described in more detail below, the space Ga allows the external housing 101 to move axially in relation to the battery holder 170 as discs 156 of the tensioning elements 152, 162 flex, however, limit the axial movement maximum relative to a distance that corresponds to the size of the Ga space. Thus, the columns 176 act as axial movement limiters or stops - the outer housing 101 can move axially downwards with respect to the battery holder 170 until the tensioner 152 contacts the columns 176 which extend from the upper wall 171 and the outer housing 101 can move axially upwards relative to the battery holder 170 until the tensioner 162 contacts the columns 176 extending from the bottom wall 172. The minimum axial height of the space Gg between the ends 127b, 143b of guides

127, 143, respectively, is greater than zero when the columns 176 extending from the wall 171 are axially supported on the tensioning element 152, thereby preventing the ends 127b, 143b from coming into contact with each other.

[0067] Referring now to Figures 7, 8 and 11, the body 173 has sides 173a, 173b that extend axially between the walls 171, 172 and an inner semi-cylindrical radial surface 177 that extends circumferentially between sides 173a, 173b. Surface 177 defines a receptacle 178 sized and shaped to receive the removable battery 190. The opening of receptacle 178 radially opposite surface 177 is circumferentially aligned with the rectangular recesses 174 of walls 171, 172. A shoulder 179a is positioned along and extends radially into surface 177. The shoulder 179a is an axially positioned proximal wall 172 and extends circumferentially between sides 173a, 173b. A plurality of axially spaced tabs 179b are located along each side 173a, 173b. Flaps 179b extend circumferentially from sides 173a, 173b. As best shown in Figure 11, battery 190 is seated in receptacle 178 against surface 177 and positioned axially between wall 171 and shoulder 179a, which restricts and / or prevents axial movement of battery 190 in relation to support 170. To accommodate the thermal expansion of the battery 190 and taking into account the tolerances (for example, the tolerance in the length of the battery 190), the axial distance between the wall 171 and the shoulder 179a is preferably greater than the length of the battery 190 and no more than 2.0 mm longer than battery length 190 and, more preferably, no more than 1.0 mm longer than battery length 190 and, even more preferably, about 0.5 mm longer than the length of battery 190. Flaps 179b extend circumferentially around battery 190, thereby keeping battery 190 inside receptacle 178. Flaps 179b are resilient elements that can be flexed outwardly to pass the battery 190 between them during insertion or removal of battery 190 from receptacle 178.

[0068] With reference now to Figures 7-11, as previously described, the sensor element 180 is a flat disk positioned inside the flange 161 with the button 164 and the lip 166 in contact with the upper surface of the element 180 and the shoulder 117 and fingers 163 in contact with the lower surface of the element 180. The radially outer periphery of the element 180 is, in general, kept stationary in relation to the outer housing 101, however, the central portion of the element 180 supports the weight of the support of the battery 170 and the components mounted on it and in addition, can be deflected by button 164. In this mode, the sensor element 180 is made of a metallic disk (for example, brass) that has one or more layers of a piezoelectric ceramic material ( for example, lead zirconate titanate (PZT)) positioned on it. When mechanical stress is applied to the sensor element 180 due to deformation or deflection, the piezoelectric ceramic material generates an electrical potential (piezoelectric effect. The sensor element 180 is electrically coupled to the wired circuit board 195, so that the generated electrical potential the piezoelectric ceramic material is detected and measured by the electronic components housed on the circuit board 195 and stored in memory on the circuit board 195.

[0069] With reference now to Figures 12 and 13, the battery 190 has a cylindrical shape and is coupled to the circuit board 195 with a pair of flaps 191. In particular, the flaps 191 are positioned at the ends of the battery 190 and are welded to battery 190. Guides 191 are made of metal (for example, nickel-plated stainless steel or nickel-plated steel) and allow a physical and electrical connection between battery 190 and circuit board 195. Thus, guides 191 allow battery 190 supply power to circuit board 195 and the various functions performed by components of board 195 during seismic surveying operations and allow plate 195 to supply power to battery 190 during inductive charging operations.

[0070] In this mode, each tab 191 is the same. More specifically, each flap 191 is formed from relatively thin sheet. The sheet is stamped and then folded, so that each flap 191 includes a generally flat base 192, a pair of supports 193 extending perpendicularly from the sides of the base 192 and a tip 194 extending from each support

193. Each base 192 is positioned flush against the corresponding end of battery 190 and welded to it. The tips 194 of each flap 191 extend across the circuit board 195 and are welded to it.

[0071] With reference now to Figures 3 and 11, the battery 190 and the circuit board 195 are fixedly coupled to the flaps 191 and then this set is releasably coupled to the battery holder 170, seating the battery 190 in receptacle 178, as previously described with plate 195 circumferentially aligned with recesses 174. Thus, when battery 190 is positioned in receptacle 178, the ends of plate 195 are positioned in recesses 174. Position circuit board 195 within the recesses 174 moves plate 195 away from housing 101, thereby reducing the possibility that the circuit board inadvertently contacts or rubs against housing 101. In addition, the sides of recesses 174 prevent circuit board 195 and battery 190 coupled to it rotate with respect to conveyor 140.

[0072] In this embodiment, the battery 190 is coaxially aligned with the conveyor 140 and the housing 101. As will be described in more detail below, during seismic surveys, the external housing 101 and the connecting elements 150, 160 retract axially in with respect to battery 190, circuit board 195 and battery holder 170 in response to vibrations induced by seismic waves. Thus, in this mode, battery 190, plate 195 and battery holder 170 collectively define the test mass of sensor 100. Guides 191 are designed and configured to provide sufficient stiffness and strength to prevent battery 190 and plate of circuit 195 move axially to each other. In particular, the bases 192 are generally oriented perpendicular to the axes 105, 145. Since the bases 192 are relatively thin in the axial direction, they may be prone to flex in the axial direction. However, supports 193 are oriented perpendicular to the corresponding base 192 (for example, parallel to axes 105, 145) and thus increase the stiffness and resistance of the bases 192 in the axial direction, limiting and / or preventing the flexing of the bases 192.

[0073] Circuit board 195 includes the electronic circuit of the sensor

100. The electronic circuit is coupled to the sensor element 180 and is positioned to process the result of the sensor element 180, for example, amplify, digitally sample, transmit and / or store the result of the sensor element 180. In addition, an LED 196 and a photodiode 197 is mounted on circuit boards 195 and coupled to electronic circuits. LED 196 and photodiode 197 are positioned adjacent to each other on the face of circuit board 195 immediately adjacent to end 143a of light guide 143. Together, the upper part 121, light guides 127, 143, LED 196 and photodiode 197 allows bidirectional data communication to / from circuit board 195. In particular, a device external to sensor 100 can communicate wirelessly with circuit board 195 by transmitting light from the external device over the top 121 and guide 127 to end 127b, through space Gg from end 127b to end 143b, through guide 143 to end 143a and through the space between end 143a and photodiode 197 to photodiode 197; and circuit board 195 can communicate wirelessly with the external device by transmitting light from LED 196 through the space between LED 196 and end 143a on guide 143, through guide 143 to end 143b, through space Gg from end 143b to end 127b and through guide 127 and top 121 to the external device.

[0074] During seismic surveys, a plurality of sensors 100 are placed on or on the surface of the ground (for example, in place of sensors 64, 66, 68 in system 50). Each sensor 100 can, for example, be attached to a pin which is pushed into the ground. Alternatively, the entire sensor 100 can be buried or placed deep in a well. Regardless of how sensors 100 are coupled to the ground, each sensor 100 is preferably positioned with axis 105 oriented in a generally vertical direction. The tensioning elements 152, 162 flex under the weight of the test piece (for example, the weight of the battery pack 190, plate 195 and battery holder 170), thereby transferring the weight of the test piece to the element sensor 180 via the button

164.

[0075] The arrival of a compression seismic wave causes the outer housing 101 and the components to be fixedly coupled (for example, coil assembly 130, body 151 and mounting flange 153 of the upper connection element 150 and flange mounting element 161 of the lower connecting element 160) to move and retract in a generally vertical direction. The inertia of the test mass inside the external housing 101 (for example, the battery pack 190, plate 195 and battery holder 170) causes the test mass to resist movement with the displacement of the external housing 101 and, consequently, there is axial movement of the outer housing 101 in relation to the test mass, as permitted by the tensioning elements 152, 162, walls 171, 172 and columns 176. This movement causes the tensioning elements 152, 162 to flex or be deflected. The button 164 is against the sensor element 180 with the sensor 100 at rest and during the reception of seismic waves. Thus, the deflection of the tensioning elements 152, 162 varies the load applied to the sensor element 180 by the button 164. The axial reciprocity of the external housing 101 in relation to the test mass generally continues as the compression seismic wave passes through the sensor 100 .

[0076] During axial alternations of the external housing 101 in relation to the test mass, the sensor element 180 is cyclically deflected by the button 164. As previously described, when mechanical stress is applied to the sensor element 180 due to deformation or deflection by the button 164, the piezoelectric ceramic material generates an electrical potential (piezoelectric effect). The electrical potential is connected to the circuit board 195 through wires, where it is detected and can be sampled and stored in memory as a measure of the amplitude of the seismic vibration. The data stored in memory on circuit board 195 can be communicated to an external device for further consideration and analysis via LED 196, light guides 127, 143 and upper part 121, as previously described.

[0077] As previously described, circuit board 195 is part of the test mass against which the external housing 101 moves axially during the seismic survey. Thus, the outer housing 101 moves axially with respect to LED 196 and photodiode 197 on circuit board 195. The two-part light guide set including light guides 127, 143 allows bidirectional communications to / from the circuit board circuit 195, despite the relative axial movement of the external housing 101 in relation to the test mass, to the associated LED 196 and photodiode 197. In particular, the space Gg allows the light guides 127, 143 to move axially with each other as light guide 127 moves axially with outer housing 101 and light guide 143 moves axially with column 141. Thus, end 143a remains aligned with LED 196 and photodiode 197 during the relative axial movement of the outer housing 101 in relation to the evidence mass.

The coaxial alignment of the guide 127, the 144b portion of the guide 143 and the outer housing 101 (including the cap 120) ensures the alignment of the ends 127b, 141b and allows the transmission of light through the guides 127, 143, despite the relative axial movement .

In addition, the coaxial alignment of the guide 127 and the 144b portion of the guide 143 with the center of the cap 120 allows light to be transmitted through the guides 127, 143 and the cap 120, regardless of the rotational orientation of the cap 120 relative to the conveyor 140 It should also be noted that the L 143-shaped guide of the light allows the transfer of light to / from photodiode 197 and LED 196, respectively, which generally face a radial direction (usually facing axis 105 ), ensuring coaxial and centralized alignment of cover 120, guide 127 and portion 144b.

In the modalities described here, the light guide sets depend on the transmission of light via total internal reflection (Total Internal Reflection, TIR), as is known in the art.

Without being limited by this or any particular theory, for the light guide sets described here that are made of transparent polycarbonate, the light incident on an internal wall of the light guide set at an angle less than about 43 ° is reflected internally.

However, it should be considered that the angle of incidence that results in internal reflection may depend on a variety of factors, including the material of the light guide set.

[0078] As previously described, the tension elements 152, 162 allow the relative axial movement generally free of the test mass in relation to the external housing 101. In the rest position, the button 164 engages with the sensor element 180 and, in addition, the Sensor element 180 supports most or substantially the entire weight of battery 190. Consequently, sensor element 180 is subjected to tension with the test mass in the rest position. The axial reciprocity of the outer housing 101 in relation to the test mass submits the sensor element 180 to increasing and decreasing degrees of tension. The voltage variations experienced by the sensor element 180 are used to detect and measure seismic waves. However, it will be appreciated that the ceramic material of the sensor element 180 can be damaged by excessive stress. Consequently, the maximum axial movement of the outer housing 101 in relation to the specimen is limited to protect the sensor element 180 and prevent it from being excessively tensioned. In the sensor modality 100 shown and described above, the maximum axial movement of the outer housing 101 in relation to the test mass is controlled and limited by columns 176, as previously described. In addition, as previously described, the tensioning elements 152, 162 propel the test mass to the central position coaxially aligned with the outer housing

101. As a result, the specimen is radially spaced from the outer housing 101 and is, in general, prevented from moving radially in relation to the outer housing 101. Consequently, the movement of the outer housing 101 in relation to the specimen is predominantly in the axial direction and, in addition, the test mass does not inhibit or interfere with the axial movement of the external housing 101. It must be considered that the spaces Gr also limit the relative radial movement between the external housing

101 and the test mass to ensure a predominantly axial movement.

[0079] Although grooves 157 that have spiral geometries are used to increase the flexibility of the disc 156 and the tensioning element 152, 162 in the axial direction in this modality of the sensor 100, in other modalities, different approaches can be used to improve the flexibility of the disc . For example, grooves with different geometries can be used (for example, grooves that extend radially as opposed to spiral grooves). As another example, the disk of each tensioning element (e.g., disk 156 of each tensioning element 152, 162) includes radially extending radii or bridges that extend between an outer periphery of the disk and the central portion of the disk, thereby , creating a plurality of pie-shaped grooves with circumferential spacing on the disk between each pair of adjacent spokes. As another example, different materials can be used to form the disc, or the thickness or geometry of the disc may vary (for example, thinner disc), etc. As used here, the term "groove" can, in general, be used to refer to a cut or hole and, therefore, should not be interpreted as referring to a specific cut or hole geometry, unless expressly stated.

[0080] A second embodiment of a seismic sensor 200 will now be described in relation to Figures 14-21. In the second embodiment, the electrical connections between the battery and the electronic circuit are resilient and work in a similar way to the tension elements 152, 162 previously described. In general, the seismic sensor 200 can be used in any seismic survey system. For example, sensor 200 can be used for any one or more of sensors 64, 66, 68 of seismic survey system 50 shown in Figure 1 and described above. Although sensor 200 can be used in a terrestrial seismic survey system, a transition zone seismic survey system or a marine seismic survey system, it is particularly suitable for terrestrial seismic survey systems and zone seismic survey systems transition.

[0081] Referring now to Figures 14-16, in this embodiment, the seismic sensor 200 includes an external housing 201, an inductive coil assembly 230 positioned inside housing 201, a conveyor 240 positioned in housing 201 and a sensor element 180 positioned inside housing 201 and coupled to conveyor 240. Electronic circuit 195 is fixedly mounted on conveyor 240 within housing 201, however, battery 190 is configured to move axially in relation to housing 201, conveyor 240 and circuit 195. Sensor element 180, battery 190 and circuit 195 of sensor 200 are the same as previously described in relation to sensor 100. Thus, electronic circuit 195 is in the form of a circuit board (for example, PCB).

[0082] Housing 201 is substantially the same as housing 101 described above. In particular, housing 201 has a central or longitudinal axis 205, a first or upper end 201a, a second or lower end 201b and an inner chamber or cavity 202. The ends 201a, 201b are closed and the inner cavity 202 is sealed and isolated from the surrounding environment outside the sensor 200, thereby protecting the sensitive components positioned within the housing 201 from the environment (e.g., water, dirt, etc.). In addition, housing 201 includes a generally cup-shaped body 210 and an inverted cup-shaped lid 220 fixedly attached to body 210.

[0083] Body 210 has a central or longitudinal axis 215 coaxially aligned with axis 205, a first or upper end 210a and a second or lower end 210b that defines the lower end 201b of housing 201. Furthermore, body 210 includes a base 211 at the lower end 210b and a tubular sleeve 212 that extends axially upwardly from the base 211 to the upper end 110a. The base 211 closes the sleeve 212 at the lower end 210b, however, the sleeve 212 and the body 210 are opened at the upper end 210a. As a result, body 210 includes a receptacle 213 that extends axially from the upper end 210a to the base 211. The receptacle 213 forms part of the inner cavity 202 of housing 201. As best shown in Figures and 19, at the lower end of the receptacle 213 axially adjacent to the base 211, the body 210 includes an upward annular flat shoulder 214 radially adjacent to the sleeve 212 and an upward circular flat surface 216 positioned concentrically within the shoulder 214. A recess 217 is provided along a portion of the shoulder 214. As will be described in more detail below, the open upper end 210a is closed with the cap 220.

[0084] In this embodiment, the body 210 of the external housing 201 includes a pair of connectors 218a, 218b. The connector 218a is located at the base 211 and the connector 218b is located along the sleeve 212. The connector 218a includes a rectangular through hole 219a that extends radially through it and a through hole 219b that extends axially from the bottom end 210b to hole 219a. The hole 219b is internally threaded and receives, externally, the externally threaded end of a bolt used to fix the sensor 200 to the ground. Through hole 219a allows a cable or the like to be connected to sensor 200 for storage or implantation. In particular, the cable can be folded twice and inserted through the through hole 219a. Thus, through hole 219a has a width of at least twice the diameter of the cable. The loop formed by the portion of the folded cable that extends through the through hole 219a is then placed around the sensor 200. In this way, a plurality of sensors 200 can be coupled to a single cable without side ropes, hooks or other mechanisms that can complicate the handling of multiple sensors.

[0085] A connector 218b is positioned along the outside of sleeve 212 proximal to the upper end 201a. In general, connector 218b is an alternative means of handling sensor 200 during implantation and recovery. In this embodiment, the connector 218b is an eye or hole connector to which a cable, cord, hook, carabiner or the like can be removably attached. The connector 218b can also be used in a similar way to the through hole 219a, thereby allowing a cable to be bent twice and inserted through the hole in the connector 218b. Thus, the hole in connector 218a has a width of at least twice the diameter of the cable. The loop formed by the portion of the folded cable that extends through the hole of the connector 218b is then placed around the sensor 200. In this way, a plurality of sensors 200 can be coupled to a single cable without side ropes, hooks or the like. mechanisms that can complicate the handling of multiple sensors. In this embodiment, the entire body 110 (including the base 211 and the sleeve 212) is made through injection molding.

[0086] With reference also to Figures 14-16, cover 220 has a central or longitudinal axis 225 coaxially aligned with axis 205, a first or upper end 220a that defines the upper end 201a of the housing 201 and a second or lower end 220b. In this embodiment, the lid 220 has the general shape of an inverted cup. In particular, the cap 220 includes a flat cylindrical upper part 221 at the upper end 220a and a tubular sleeve 222 that extends axially downwardly from the upper part 221 to the lower end 220b. The upper part 221 closes the sleeve 222 at the upper end 220a, however, the sleeve 222 and the cap 220 are opened at the lower end 220b. As a result, the cap 220 includes an inner chamber or cavity 223 that extends axially from the lower end 220b to the upper part 221. An annular flange 226 extends radially outwardly from the sleeve 222 proximal to the lower end 220b. An annular recess 227 is located along the bottom surface of flange 226.

[0087] As best shown in Figures 15 and 16, the lid 220 is fixedly attached to the body 210. In particular, the lid 220 is coaxially aligned with the body 210 with the lower end 220b of the lid 220 seated on the upper end 210a of the body 210 and the upper end 210a of the body 210 seated in the annular recess 227 of the flange 226. The body 210 and the cover 220 are dimensioned so that an interference fit is provided between the lower end 220b of the cover 220 and the upper end 210a of body 210 and an interference fit is provided between the upper end 210a of body 210 and recess 227. In this embodiment, body 210 and cover 220 are made of the same material (polycarbonate) and, therefore, can be welded by ultrasound together to securely attach cover 220 to body 210. More specifically, an annular ultrasonic weld W210-220 is formed between the opposite radially outer surface and the radially inner surface of the gloves 222, 212, respectively, at the ends 220b, 210a. The weld W210-220 defines an annular seal between the cap 220 and the body 210 that prevents fluid communication between the cavities 213, 223 and the environment around the sensor 200.

[0088] With reference also to Figures 15 and 16, the inductive coil assembly 230 is used to inductively charge the battery 190 from the outside of the sensor 100 (for example, wireless). In this embodiment, the coil assembly 230 is substantially the same as the inductive coil assembly 130 previously described, except that the coil assembly 230 does not include locks 137 or guides 138. Thus, the coil assembly 230 includes the annular body 131 and the coil 136 wrapped around the body 131. The body 131 is positioned on the upper portion of the conveyor 240. The coil 136 is electrically coupled to the circuit board 195 with wires (not shown) that allow the current transfer to the plate circuit 195 which, in turn, charges battery 190 during charging operations.

[0089] In this embodiment, the conveyor 240 supports the circuit board 195 and a light guide 228 inside the body 211 of the external housing 210 and, in addition, the conveyor 240 operates on the sensor element 180 in response to vibrations induced by seismic waves . However, unlike the sensor 100 previously described, in this embodiment, the battery 190 is positioned movably within the conveyor 240. In particular, the conveyor 240, the circuit board 195 and the light guide 228 are fixedly coupled to the outer housing 201 and do not move relative to the outer housing 210, however, the battery 190 is movably coupled to the carrier 240 and therefore the battery 190 can move axially with respect to the carrier 240, to the circuit board 195, light guide 228 and external housing 201.

[0090] As best shown in Figures 15 and 16, the conveyor 240 has a central or longitudinal axis 245 coaxially aligned with the axis 205, a first end or upper end 240a that extends through the inductive coil assembly 230, a second end or lower 240b axially adjacent to the base 211 and a radially outer surface 241 extending axially from the upper end 240a to the lower end 240b.

The outer surface 241 slidably engages the outer housing 201 between the ends 240a, 240b.

In particular, the outer surface 241 includes a first cylindrical surface 241a proximal to the upper end 240a, a second cylindrical surface 241b axially adjacent to surface 241a and a third cylindrical surface 241c axially adjacent to surface 241b and extending axially from the lower end 240b.

Thus, the cylindrical surface 241b is axially positioned between surfaces 241a, 241c.

Surfaces 241a, 241b, 241c are positioned at different radii - surface 241a is positioned at a smaller radius than surface 241b and surface 241b is positioned at a smaller radius than surface 241c.

Thus, upward planar annular shoulders extend radially between each pair of axially adjacent surfaces 241a, 241b, 241c.

The surface 241a extends through and slidably engaged with the cylindrical inner surface of the body 131, the surface 241b is positioned within and slidably engaged with the cylindrical inner surface of the cap 220 and the surface 241c is positioned within and slidably engaged. on the inner cylindrical surface of sleeve 212. The radial fit of these surfaces prevents the conveyor 240 from moving radially or laterally in relation to the outer housing 201. In this embodiment, the inner cylindrical surface of sleeve 212 includes a pair of splines that extend axially and slidingly engage in a corresponding pair of axially extending recesses located on the outer surface 241c.

The engagement of these coincident grooves and recesses prevents the conveyor 240 from rotating about the axis 205 in relation to the external housing 201.

[0091] Although the surfaces 241a, 241b, 241c of the outer surface 241 are described as cylindrical, it should be considered that the outer surface 241 of the conveyor 240 may include cavities or recesses (for example, to reduce its weight, facilitate its manufacture through injection molding, etc.). In addition, the outer surface 241 includes a flat surface 242 that extends axially from the upper end 240a to the lower end 240b. The flat surface 242 is oriented parallel to the axis 245, is displaced radially from the axis 245 and constitutes a face against which the circuit board 195 can be mounted. Despite the above, the outer surface 241 slidily engages each of the cap 211, the sleeve 212 and the body 131 at an angular distance of at least 180º measured around the axes 205, 245, which prevents the conveyor 240 from moving. move radially and laterally in relation to the outer housing

201.

[0092] The conveyor 240 has an axial length that is substantially the same as the axial length of the cavity 223. Thus, the upper end 240a engages the upper part 221 of the cover 220 and the lower end 240b is seated against the sensor disk 180 o which, in turn, is supported by the shoulder 214. More specifically, the conveyor 240 is compressed axially between the lid 220 and the outer housing 210. As a result, the conveyor 240 cannot move axially with respect to the outer housing 201.

[0093] With reference also to Figures 15 and 16, the carrier 240 includes a recess or pocket 244 which extends radially inward from the outer surface 241 and, in particular, from the flat surface

242. The pocket 244 is defined by an upper end surface 246, a lower end surface 247 and a cylindrical surface 248 that extends axially between the end surfaces 246, 247. The battery

190 is positioned inside pocket 244, but does not contact the carrier

240. In particular, the dimensions of the pocket 244 are greater than the dimensions of the battery 190 (for example, the radius of the surface 248 is greater than the external radius of the battery 190 and the axial distance between the end surfaces 246, 247 is longer than battery length 190). In this embodiment, battery 190 is oriented parallel to axes 205, 245, however, it is slightly offset radially from axes 205, 245. In particular, the central axis of battery 190 is offset radially from axes 205, 245 by about 1.0 to 1.5 mm.

[0094] Referring now to Figures 15-20, an annular recess 250 extends radially out of pocket 244 and to surface 248 proximal to the upper terminal surface 246 and an annular recess 251 extends radially out of pocket 244 and to the surface 248 proximal to the lower terminal surface 247. As best shown in Figures 18 and 20, a rectangular hole 252 extends radially from recess 250 and surface 248 to the outer surface 241c proximal to the upper terminal surface 246 and a rectangular hole 253 extends radially from recess 251 and from surface 248 to outer surface 241c proximal to the lower end surface 247. As best shown in Figures 17 and 18, end surface 246 is axially spaced above recess 250 and in hole 252 and , as best shown in Figures 19 and 20, the end surface 247 is axially spaced below the recess 251 and in the hole 253.

[0095] Referring now to Figures 16 and 18, the curved and elongated L-shaped light guide 228 is fixedly attached to the bracket

240. In this embodiment, the light guide 228 is integral and monolithically formed with the support 240. The light guide 228 has a first end 228a proximal to the circuit board 195, a second end 228b that engages or is immediately adjacent to the upper part 221, a first or horizontal portion 229a extending radially from end 228a, a second or vertical portion 229b extending axially from end 143b and a substantially 90 ° curve or curvature extending between portions 229a, 229b . The horizontal portion 229a extends across the surface 241a and the vertical portion 229b extends to the upper end 240a. In addition, the vertical portion 229b is coaxially aligned with the conveyor 240 and the housing 201. As will be described in more detail below, the light guide 228 wirelessly communicates data to / from the circuit board 195 through the upper 221. To facilitate the transmission of light, the light guide 228 and the upper part 221 are made of a transparent material. In this embodiment, the entire cover 220 (including the upper part 221 and the sleeve 222) and the guide 228 are made of a transparent polycarbonate.

[0096] Referring now to Figures 19 and 20, a generally circular recess 260 is located at the lower end 240b of the conveyor 240. The recess 260 is coaxially aligned with the battery 190 and the pocket 244 and has a slightly smaller radius than the conveyor radius 240 at the lower end 240b. As a result, the lower end 240b of the conveyor 240 is a downwardly facing flat annular surface. The recess 260 extends axially from the lower end 240b to an annular flange 261 axially positioned between the recess 260 and the pocket 244. The upper flat surface of the flange 261 defines the lower terminal surface 247 of the pocket 244 and the lower flat surface of the pocket. flange 261 defines the upper end of recess 260. A central hole 262 extends axially through flange 261 and a cylindrical column 263 is positioned coaxially in hole 262. Recess 260, hole 262 and column 263 are coaxially aligned with the battery 190. A thin arm or blade 264 extends between the column 263 and the flange 261, thereby keeping the column 263 in position within the hole 262.

As will be described in more detail below, the column 263 can move axially freely within the hole 262, as the outer housing 201 and the conveyor 240 retract axially. The thin arm that extends between the column 263 and the flange 261 does not inhibit the axial movement of the outer housing 201 and the conveyor 240 in relation to the column 263. Although the column 263 is coupled to the flange 261 with a thin arm or blade in this embodiment , in other embodiments, the column (for example, column 263) is not coupled to the flange and is instead attached to a battery tab (for example, tab 290 described in more detail below) or to the sensor element 180.

[0097] With reference now to Figures 16, 19 and 20, the sensor element 180 is a flat disk positioned axially between the lower end 240b and the shoulder 214. The end 240b and the shoulder 214 are positioned in the same radius and engage the periphery radially external to the upper and lower surfaces of the element 180, respectively. In addition, column 263 engages in the center of the upper surface of sensor element 180. Thus, the outer periphery of sensor element 180 is compressed and secured in the position between end 240b and shoulder 214. Thus, the radially outer periphery of element 180 it is, in general, kept static in relation to the housing 201 and the conveyor 240, however, the central portion of the element 180 can be deflected with the column 263. The flat surface 216 is axially spaced below the sensor element 180 (for example, there is a space between the flat surface 216 and the sensor element 180), thus allowing the column 263 to deflect or flex the central portion of the element 180. As previously described, the sensor element 180 is made of a metallic disk ( for example, brass) with one or more layers of a piezoelectric ceramic material (for example, lead zirconate titanate (PZT)) positioned on it. When mechanical stress is applied to the sensor element 180 due to deformation or deflection, the piezoelectric ceramic material generates an electrical potential (piezoelectric effect). The sensor element 180 is electrically coupled to the wired circuit board 195, so that the electrical potential generated by the piezoelectric ceramic material is detected and measured by the electronic components housed on circuit board 195 and stored in memory on circuit board 195. One Since the axial movement of the sensor element 180 in relation to the column 263 while the column 263 engages the sensor element 180 induces tension in the sensor element 180, the column 263 can also be referred to here as a pusher or driver.

[0098] Referring now to Figures 16, 18 and 21, battery 190 is cylindrical in shape and is coupled to circuit board 195 with a pair of tabs 290. In particular, tabs 290 are positioned at the ends of battery 190 and they are spring loaded to axially compress battery 190 between them. Guides 290 are made of metal (for example, steel) and allow a physical and electrical connection between battery 190 and circuit board 195. Thus, guides 290 allow battery 190 to supply power to circuit board 195 and the various functions performed by the plate 195 components during seismic surveying operations and allows the plate 195 to supply power to the battery 190 during inductive charging operations.

[0099] In this embodiment, each flap 290 is a semi-rigid and resilient element through which the battery 190 is supported within the pocket 244 of the carrier 240. As best shown in Figure 21, each flap 290 comprises a disk 291, a plurality of tips 292 extending laterally from disk 291 and a connector 293 extending radially from disk 291. As best shown in Figure 21, disk 291 has a semi-cylindrical shape that includes a straight edge 291a and a semicircular edge 291b that extends from side 291a. The tips 292 extend from the edge 291a and the connector 293 extends from the semicircular edge 291b of the opposite ends 292.

[00100] For the sake of clarity and further explanation, the guide 290 coupled to the upper part of the battery 190 can be termed as the upper guide 290 and the guide 290 coupled to the lower part of the battery 190 can be termed as the lower guide 290. According to shown in Figures 15-20, the semicircular edge 291b of the upper tab 290 is seated in the recess 250 of the support 240 and the semicircular edge 291b of the lower tab 290 is seated in the recess 251 of the support 240. As best shown in Figures 18 and 20, the connector 293 of the upper flap 290 is seated in the corresponding hole 252 and the connector 293 of the lower flap 290 is seated in the corresponding hole 253. The positioning of the edges 291b in the recesses 250, 251 keeps the outer periphery of the flaps 290 static or fixed in relation to the conveyor 240 and the outer housing 201 and the positioning of the connectors 293 in the holes 252, 253 prevents the flaps 290 from rotating in relation to the conveyor 240 and outer housing 201. The ends 292 of each flap 290 extend through circuit board 195 and are welded to it.

[00101] - "Now referring to Figures 18 and 20, each flap 290 includes a central projection 296 that extends axially from them and a plurality of cuts or grooves uniformly spaced circumferentially through cuts or grooves 297 positioned radially between the projection 296 and edges 291a, 291b. The flaps 290 are oriented so that the central projections 296 face the battery 190. In addition, the projection 296 of the upper flap 290 is fixedly attached to the upper end of the battery 190 and the central projection 296 of the lower flap 290 is fixedly attached to the bottom end of the battery 190. In this embodiment, the 296 projections are welded by points on the ends of the battery

190. The upper end of the column 263 contacts the center of the lower flap 290.

[00102] Each 297 slot extends axially through the flap

290. In addition, each slot 297 spirals radially outward as it moves from a central projection radially proximal to the edges 291a, 291b. In this embodiment, four grooves 297 are provided, each pair of circumferentially adjacent inner ends of the grooves 297 is angularly spaced at 90º to each other with respect to the axis 245, each pair of circumferentially adjacent outer ends of the grooves 297 is angularly spaced at 90º to the axis 245 and each groove 297 extends along a spiral angle measured around axis 245 between its ends of about 360 ”. The radially internal ends of the grooves 297 are radially adjacent projections 296.

[00103] As previously described, the tabs 290 provide electrical couplings between the battery 190 and the circuit board 195. In addition, the tabs 290 function as bending or tensioning elements in a similar manner to the tensioning elements 152, 162 previously described. Consequently, flaps 290 can also be referred to as bending elements or tensioners. In particular, the flaps 290 are resilient flexible elements that flex and deform elastically in response to the relative axial movement of the outer housing 201 and the conveyor 240 with respect to the battery 190 and the radially driven battery 190 to a central or concentric position within the pocket 244 radially spaced from the conveyor

240. In particular, the presence of the spiral slots 297 increases the flexibility of the flap 290 in the region along which the slots 297 are positioned, thus allowing the region to flex in the axial direction (up and down) with relative facility. Spiral grooves 297 also increase the flexibility of each flap 290 in the radial direction. However, the spiral grooves 297 do not allow the tabs 290 to flex so easily in the radial direction. Due to the relatively high degree of flexibility of the flaps 290 in the axial direction, when an axial load is applied to the flaps 290 by the conveyor 240 or battery 190, the grooves 297 generally allow a relative free axial movement between the central projections 296 and the edges 291a , 291b. However, due to the more limited flexibility in the radial direction, when a radial load is applied to the flaps 290 by the carrier 240 or the battery 190, the grooves 297 generally resist relative radial movement between the central projections 296 of the flaps 290 and the edges 291a, 291b and the tabs 290 drive the battery 290 and the conveyor 240 back into substantial coaxial alignment with the axes 205, 245.

[00104] Battery 190 is aligned coaxially with pocket 244 and oriented parallel to conveyor 240 and housing 201. As will be described in more detail below, during seismic lifting operations, conveyor 240 and housing 201 make an axial reciprocal movement relative to battery 190 and column 263 in response to vibrations induced by seismic waves. The axial reciprocity of the carrier 240 and the housing 201 relative to the battery 190 causes the flaps 290 to flex. Thus, in this embodiment, the test mass of the sensor 200 includes the battery 190, the column 263 and the flaps 290 (or at least a part of them that is static in relation to the battery 190).

[00105] Circuit board 195 includes the electronic circuit of the sensor

200. The electronic circuit is coupled to the sensor element 180 and is positioned to process the result of the sensor element 180, for example, amplify, digitally sample, transmit and / or store the result of the sensor element 180. In addition, LED 196 and the photodiode

197 are positioned adjacent to each other on the face of circuit board 195, immediately adjacent to end 228a of light guide 228. Together, the upper part 221, light guide 228, LED 196 and photodiode 197 allow bidirectional communication data to / from circuit board 195. In particular, a device external to sensor 200 can communicate wirelessly with circuit board 195 by transmitting light from the external device through the top 221 and the guide 228 to the photodiode 197; and the circuit board 195 can communicate wirelessly with the external device by transmitting light from LED 196 through the guide 228 and from the top 221 to the external device.

[00106] During seismic surveys, a plurality of sensors 200 are coupled to the surface of the ground (for example, in place of sensors 64, 66, 68 in system 50). Each sensor 200 can, for example, be attached to a pin which is pushed into the ground. Alternatively, the entire sensor 200 can be buried or placed deep in a well. Regardless of how sensors 200 are coupled to the ground, each sensor 200 is preferably positioned with axis 205 oriented in a generally vertical direction.

[00107] —A seismic compression wave causes the external housing 201 and fixedly coupled components (for example, coil assembly 230, conveyor 240, circuit board 195, light guide 228) to move in one generally vertical direction. The inertia of the specimen inside the outer housing 201 (battery 190) causes the specimen to resist movement with the displacement of the outer housing 201 and the conveyor 240 and, consequently, the outer housing 201 and the conveyor 240 make a reciprocal movement axially in relation to the test mass, as allowed by the guides 290. This movement causes the guides 290 to flex or be deflected and the load of the test mass is absorbed by the sensor element 180. The axial reciprocity of the external housing 201 and of the carrier 240 with respect to the test mass generally continues when the compression seismic wave passes through the sensor 200.

[00108] During the axial reciprocal movements of the outer housing 201 and the conveyor 240 in relation to the test mass, the sensor element 180 is deflected cyclically by the column 263. As previously described, when the mechanical stress is applied to the sensor element 180 due to from deformation or deflection by column 263, the piezoelectric ceramic material generates an electrical potential (piezoelectric effect). The electrical potential is connected to the circuit board 195 through wires, where it is detected and can be sampled and stored in memory as a measure of the amplitude of the seismic vibration. The data stored in memory on circuit board 195 can be communicated to an external device for further consideration and analysis via LED 196, light guide 228 and upper part 221 as previously described.

[00109] As previously described, the tabs 290 allow a relative axial movement generally free of the test mass in relation to the external housing 201. In the resting position, the column 263 engages the sensor element 180 and, in addition, the sensor element 180 supports most or substantially all of the weight of the test mass. The axial reciprocity of the external housing 201 and the conveyor 240 in relation to the test mass subject the sensor element 180 to increasing and decreasing degrees of tension. The variations in stress experienced by the sensor element are used to detect and measure seismic waves. However, it will be appreciated that the ceramic material of the sensor element 180 can be damaged by excessive stress. Consequently, the maximum axial movement of the outer housing 201 in relation to the specimen is limited to protect the sensor element 180 and prevent it from being excessively tensioned. In the modality of the sensor 200 shown and described above, the maximum axial movement of the external housing 201 for the specimen is controlled and limited by the support 240 - the flaps 290 can deflect axially upwards until the upper flap 290 axially engages the support 240 at the upper end 246 of the pocket 244 and the flaps 290 can deflect axially downward until the lower flap 290 axially engages the support 240 at the lower end 247 of the pocket 244. In addition, as previously described, the flaps 290 deflect the test mass to the central position aligned coaxially to the outer housing 201 and the support 240. As a result, the conveyor 240 is radially spaced from the specimen and is generally prevented from moving radially with respect to the specimen. Consequently, the movement of the outer housing 201 and the conveyor 240 with respect to the specimen is predominantly in the axial direction, and furthermore, the specimen does not inhibit or interfere with the axial movement of the conveyor 240 and the housing 201. The radial space between the specimen and the cylindrical surface 241b of the pocket 244 allow the conveyor 240 and the outer housing 201 to move radially and laterally in relation to the specimen as the flaps 290 flex, but limit relative radial and lateral movement maximum. In particular, the conveyor 240 and the housing 201 can move radially and laterally in relation to the specimen until the specimen engages the surface 248 that defines the pocket 244. Thus, the surface 248 functions as a movement limiter or radial stop .

[00110] If desired, an impact protection element can be provided around the battery 190. The protection element protects the battery 190 from physical damage if it impacts the surfaces inside the housing 201 during lateral movement in relation to the carrier 240 / housing 201. For example, during the lateral movement of the battery 190 in relation to the carrier / housing, the battery can impact circuit board 195, which can damage the battery. The protective element may be in the form of a protective sheath strong enough to withstand repeated impacts on the battery or, beneficially, one or more movement limiters or stops positioned on the external surface of the battery 190 or positioned inside the housing 201 between the battery and the circuit board, so that the side impact between the battery and the circuit board 195 is prevented. An example of a movement limiter or stop is one or more clamps with resilient arms that extend at least partially around the battery 190.

[00111] Although grooves 297 with a spiral geometry are employed to increase the flexibility of the disk 291 and the tensioning element 290 in the axial direction in this modality of the sensor 200, in other modalities, different approaches can be used to improve the flexibility of the disk. For example, grooves with different geometries can be used (for example, grooves that extend radially as opposed to spiral grooves). As another example, the disc of each tensioning element (for example, disc 291 of each flap 290) includes radii or radially extending bridges that extend between an outer periphery of the disc and the central part of the disc, thereby creating a plurality of pie-shaped grooves circumferentially spaced between each pair of adjacent spokes. Figure 22 illustrates an alternative embodiment of a guide 390 that works in the same way as the guide 290 previously described and that can be used in place of the guide

290. As shown in Figure 22, in this embodiment, guide 390 comprises a disc 391 and a plurality of tips 292, as previously described, extending laterally from the disc

391. Instead of the spiral slots 297, disk 391 of flap 390 includes a plurality of uniformly spaced circumferential spokes 393 extending radially from a central portion of disk 391 to the outer periphery of disk 391. As another example, different materials can be used to form the disc, the thickness or geometry of the disc may vary (eg thinner disc), etc.

[00112] In the mode of sensor 200 shown and described above, conveyor 240 is a monolithic component of one piece. However, in other embodiments, the carrier (e.g., carrier 240) comprises more than one section and such sections may be discontinuous. In still other embodiments, the carrier is absent. In such embodiments, the other sensor components (for example, circuit board 195, tabs 290 and sensor element 180) can be coupled directly to the outer housing (for example, outer housing 201) or by means of individual conveyor components.

[00113] Although preferred modalities have been shown and described, modifications can be made by those skilled in the art without departing from the scope or teachings here. The modalities described here are only exemplary and are not limiting. Many variations and modifications of the systems, devices and processes described here are possible and are within the scope of the invention. For example, the relative dimensions of various parts, the materials from which the various parts are made and other parameters can be varied. Consequently, the scope of protection is not limited to the modalities described here, however, it is limited only by the following claims, the scope of which must include all equivalents of the subject of the claims. Unless expressly stated otherwise, the steps in a method claim may be performed in any order.

Quoting identifiers, such as (a), (b), (c) or (1), (2), (3), before the steps of a method claim are not intended to specify and do not specify a specific order for the steps, but are used to simplify a subsequent reference to those steps.

Claims (41)

1. Seismic sensor characterized by comprising: an external housing that has a central axis, an upper end, a lower end and an internal cavity; a test mass movably positioned in the internal cavity of the external housing, where the external housing is configured to move axially in relation to the test mass; a first tensioning element positioned in the internal cavity and positioned axially between the test mass and one of the ends of the external housing, where the first tensioning element is configured to flex in response to the axial movement of the external housing in relation to the test mass, in that the first tensioning element comprises a disk that includes a plurality of circumferentially spaced grooves extending axially through them; a sensor element positioned in the internal cavity and positioned axially between the first tensioning element and one of the ends of the external housing, wherein the sensor element comprises a piezoelectric material configured to deflect and generate a potential in response to the axial movement of the external housing in relation to the test mass and flexion of the first tensioning element. 2. Seismic sensor, according to claim 1, characterized by the fact that the first tensioning element is axially positioned between the test mass and the lower end of the external housing. Seismic sensor, according to claim 1 or claim 2, characterized in that the plurality of circumferentially spaced grooves spiral radially outwardly from a center of the tensioning element. 4. Seismic sensor according to claim 1 or claim 2, characterized in that the plurality of circumferentially spaced grooves is circumferentially positioned between radially extending spokes that connect a center of the tensioning element and an outer periphery of the tensioning element. 5. Seismic sensor according to any one of the preceding claims, characterized by the fact that the sensor element is positioned between the first tensioning element and the second end of the external housing. 6. Seismic sensor, according to claim 5, characterized by the fact that a button extends axially from a central portion of the tensioning element, where the button contacts the sensor element and is configured to apply an axial load to the element sensor in response to the flexing of the first tensioning element and the axial movement of the external housing in relation to the test mass. 7. Seismic sensor, according to claim 6, when dependent on claim 3, characterized by the fact that each spiral groove has a radially internal end that is positioned radially close to the button. Seismic sensor according to any one of claims 5 to 7, characterized in that a driver is positioned axially between a central portion of the first tensioning element and the sensor element, in which the driver comes into contact with the sensor element and it is configured to apply an axial load to the sensor element in response to the flexing of the first tensioning element and to the axial movement of the external housing in relation to the test mass. 9. Seismic sensor according to any one of the preceding claims, characterized by the fact that a radially external periphery of the sensor element is axially fixed in relation to the external housing. 10. Seismic sensor, according to any of the previous claims, characterized by also comprising: electronic circuits coupled to the sensor element, the electronic circuits being configured to detect the potential generated by the piezoelectric material; and a power source configured to supply electrical energy to the electronic circuit; where the test mass includes the power supply. 11. Seismic sensor, according to claim 10, characterized by the fact that the test mass includes the electronic circuit. 12. Seismic sensor, according to claim 10, characterized by the fact that the test mass consists of the power supply. 13. Seismic sensor according to any one of claims 10 to 12, characterized by the fact that the first tensioning element electrically couples the power supply to the electronic circuit. 14. Seismic sensor, according to claim 13, characterized by the fact that the first tensioning element mechanically couples the power supply to an electronic circuit board to support the power supply in the internal cavity of the external housing. Seismic sensor according to any one of claims 10 to 14, characterized in that it also comprises a set of light guides configured to transmit light from an electronic circuit LED and / or transmit light to an electronic circuit photodiode. 16. Seismic sensor according to claim 15, characterized by the fact that the set of light guides includes a first light guide fixedly attached to the specimen and a second light guide fixedly attached to the external housing . 17. Seismic sensor, according to claim 16, characterized by the fact that the second light guide is coaxially aligned with an upper cover of the external housing. 18. Seismic sensor, according to any of the previous claims, characterized by the fact that the first tensioning element is configured to restrict the movement of the external housing in relation to the test mass for axial reciprocity. 19. Seismic sensor, according to claim 18, characterized by the fact that the first tensioning element is configured to radially impel the test mass in coaxial alignment with the external housing. Seismic sensor according to claim 2 or any one of claims 3 to 19, when dependent on claim 2, characterized in that it further comprises a second tensioning element positioned in the internal cavity and axially positioned between the test mass and the upper end of the outer housing, in which the second tensioning element is configured to flex in response to the axial movement of the outer housing in relation to the test mass and in which the second tensioning element comprises a disk that includes a plurality of circumferentially spaced spiral grooves extending axially through it. 21. Seismic sensor, according to claim 20, characterized by the fact that the first tensioning element and the second tensioning element are configured to restrict the movement of the external housing in relation to the test mass for axial reciprocity. 22. Seismic sensor according to claim 21, characterized by the fact that the first tensioning element and the second tensioning element are configured to propel the test mass radially in coaxial alignment with the external housing. 23. Seismic sensor according to any one of claims 20 to 22, characterized in that the second tensioning element electrically and mechanically couples the power supply to the electronic circuit and in which the first tensioning element electrically and mechanically couples the source of supply to the electronic circuit. 24. Seismic sensor for seismic survey, the seismic sensor characterized by comprising: an external housing that has a central axis; a test mass movably positioned in the external housing, the test mass comprising a power supply; a disk-shaped sensor element positioned in the outer housing and configured to detect the movement of the outer housing in relation to the test mass; electronic circuits coupled to the sensor element; and a first tensioning element and a second tensioning element that support the test mass inside the outer housing, where the second tension element is axially positioned between the test mass and the sensor element, where each tension element comprises a conductive elastic disk which has a central region coupled to the test mass and a radially external periphery that can be fixedly attached to the external housing, in which each tension element is configured to flex in an axial direction and resist flexion in a radial direction and in which each tension element electrically couples the power supply to the electronic circuit. 25. Seismic sensor, according to claim 24, characterized by the fact that the sensor element is axially adjacent to the second tensioning element and in which the sensor element is configured to deflect and generate a potential in response to the flexing of the second tensioning element. 26. Seismic sensor according to claim 25, characterized by the fact that an axial projection of the second tension element or an actuator axially positioned between the sensor element and the second tension element transfers an axial force from the second tension element to the sensor element . 27. Seismic sensor according to claim 26, characterized by the fact that the axial projection or the driver engages in a central region of the sensor element and in which an external periphery of the sensor element is fixedly coupled to the external housing. 28. Seismic sensor according to any one of the preceding claims, characterized in that the electrically conductive resilient disk of each tensioning element comprises a plurality of grooves extending axially through the disk. 29. Seismic sensor according to claim 28, characterized in that the plurality of grooves in each disc comprises a plurality of spiral grooves. 30. Seismic sensor according to any one of the preceding claims, characterized in that it further comprises a conveyor fixedly coupled to the external housing, in which the first tensioning element and the second tensioning element are fixedly coupled to the external housing and support the test mass inside the external housing. 31. Seismic sensor according to any one of the preceding claims, characterized by the fact that the electronic circuit comprises a circuit board fixedly coupled to the external housing, where each of the first tensioning element and the second tensioning element comprises connectors which extend from them and electrically connected to the circuit board to couple the electronic circuit to the power supply and in which the first tensioning element and the second tensioning element support the test mass inside the external housing. 32. Seismic sensor according to claim 24, characterized in that the conveyor includes a first connection element fixedly coupled to the external housing proximal to the first end, a second connection element fixedly coupled to the external proximal housing the second end and a battery holder positioned axially between the first connecting element and the second connecting element; wherein a battery is removably mounted on the battery holder; wherein the first tensioning element couples the battery support to the first connecting element and the second tensioning element couples the battery support to the second connecting element. 33. Seismic sensor, according to claim 32, characterized by also comprising electronic circuits coupled to the sensor element and the battery, in which the test mass includes the battery, the battery holder and the electronic circuit. 34. Seismic sensor according to any one of claims 24 to 31, characterized by the fact that the test mass consists of the power supply. 35. Seismic sensor according to any one of the preceding claims, characterized in that the sensor element comprises a piezoelectric material. 36. Method for detecting seismic waves that pass through an underground formation, the method characterized by comprising: (a) coupling a seismic survey device in contact with the ground above the underground formation, in which the seismic survey device comprises: a external housing having a longitudinal axis, an upper end, a lower end and an internal cavity; a test mass movably positioned in the internal cavity of the external housing; a first tensioning element positioned in the internal cavity and axially positioned between the test mass and the lower end of the external housing; a sensor element positioned in the internal cavity and axially positioned between the specimen and the lower end of the outer housing or the upper end of the outer housing; (b) orient the seismic survey device with the longitudinal axis of the housing in a vertical orientation; (c) moving the outer housing vertically in relation to the body in response to seismic waves; (d) flexing the first tensioning element axially in response to (c); (e) deflecting the sensor element during (d); (f) generate a signal with the sensor element indicating the vertical movement of the external housing in relation to the test mass during (c) in response to (e). 37. Method according to claim 36, characterized in that the sensor element is axially positioned between the first tensioning element and the lower end of the outer housing and in which the first tensioning element is configured to flex axially towards the element sensor during step (d). 38. The method of claim 37, further comprising: (g) driving the test mass axially upwards with the first tensioning element in response to (d). 39. Method according to claim 37, characterized by the fact that the seismic lifting device includes a second tensioning element positioned in the internal cavity and positioned axially between the test mass and the upper end of the external housing, in which the mass The test piece is supported in the external housing between the first tensioning element and the second tensioning element. 40. The method of claim 39, further comprising: (g) polarizing the test mass axially upwards with the first tensioning element and the second tensioning element in response to (d). 41. The method of claim 36, further comprising: resisting the radial movement of the external housing in relation to the test mass with the first tensioning element.